Selector



Aug- 19, 1958 P. R. GOUDY ET AL 2,

SELECTOR Filed Sept. 14, 1955 INVENTORS PAUL R. GOUDY JOSEPH J. GRIBBLE United States Patent Ofitice 2,848,584 Patented Aug. 19, 1958 SELECTOR Paul R. Goudy, Whitefish Bay, and Joseph J. Gribble,

Fox Point, Wis., assi'gnors to Square D Company, Detroit, lVIich., a corporation of Michigan A 'i lieatio'n Se tember 14, 1955, Serial No. 534,348 13 Claims. (Cl. 200'-' -166) The present invention relates to a selector and more particularly, to a selector having an indexing operating member for controlling and indicating the condition of the selector mechanism. I

Although a selector of the type herein described has many applications, it is particularly useful in selectively controlling the operation of electrical switches for equipment requiring a conveniently accessible control station wherein the condition of operation is positive and plainly indicated to assure the desired functioning of the equipment.

An object, therefore, of the present invention is the provision of a selector which will provide for all the requirements stated above.

Another object is to provide a selector which is inexpensive to manufacture, having a minimum number of simple parts which are easily assembled.

A further object of the invention 'is the provision of a selector which is durable but also easily repairable.

Still another object is to provide an inexpensive indexing arrangement providing positive and accurate action and sufiiciently rugged to withstand repeated operation and abuse.

A still further object of the invention is the provision of a selector switch employing a simplified contact operator and indexing member.

Another object is to provide a detent spring which is inexpensive to manufacture but whose construction provides ample resiliency for producing an indexing operation.

Further objects and features of the invention will be. readily apparent to those skilled in the art from the specification and appended drawing illustrating certain preferred embodiments in which:

Figure 1 is a perspective view of a selector switch embodyiiig the invention.

Figure 2 is a rear View of the selector switch with the cover plate removed.

Figure 3 is a sectional view of the selector switch of Figure 2 with the contacts and contact mounting removed.

Figure 4 is an enlarged sectional View of the detent spiing before the index member is placed in position to deflect the spring.

Figure 5 is another enlarged sectional view of the detent spring deflected or compressed by an applied force along the line indicated by the arrow.

Referring now to the drawings, wherein like reference characters designate like or corresponding parts throughout the several views, there is shown in Figure l which illustrates a preferred embodiment, a selector .switch 9 mounted in an insulating base or housing 12 having a removable cover plate 14'. An eccentric cam or contact operator is connec'ted'to a control knob by 'a recessed index member 22 whereby the operating'condi'tion of the switch contacts is indicated by the position of the control knob 10 and the indicia 15 on the raised portion of' the base adjacent the control knob.

A"siiitabl'e number of control loads 13 are'connected'to the contacts inside the housing 12, pass through slots arranged near the contact terminalsv on one side of the housing, and directed off to the associated equipment to be controlled.

The switch structure arrangement of the selector is shown in Figure 2 and includes a pair of movable contacts 18 having leaf spring supports fastened to a mounting bracket 17 which is in turn secured to the base 12 in the central recess 16. Cooperating with the movable contacts are a pair of stationary contacts 19 mounted on the insulating base 12 in recess 16; the stationary contacts are mounted in an opposing relation on either side of the movable contacts 18 whereby an operator member 23 operating the movable contacts closes the associated circuit connected to the base plate. The movable contacts in cooperation with the stationary contacts 19 form a single pole double throw switch wherein each movable contact is controlled individually by the operator 23.

The control knob 10, the cylindrical index member 22 and operator 23, form :a unitary construction wherein the indexing member 22 has slots or recesses 25, formed in the periphery which cooperate with a detent spring 20 housed in a rectangular compartment 24 which opens into the bore or chamber in the base 12. Diametrically opposite the compartment 24, in the cylindrical wall 27, an opening taper 34 is provided for facilitating the insertion of the-cylindrical index member which must pass the edge of the spring 20 but compress or deflect the spring into a statically loaded condition upon seating in the base 12.

Referring now more particularly to the detent spring 20 as shown in Figure 4, 'a'sectional view of the compartment and spring discloses the details of the spring construction as well as the seating of the spring in the chamber 24 before compression or deflection by the index member 22. The detent spring 20 is preferably formed from non-ferrous material requiring no heat treatment which has a low elastic limit but provides suflicient spring pressure or resiliency to position the operator 23 by recesses '25 and the index member 22. The dimensions of the spring 22 are limited depending upon the size of the compartment wherein the raised center section 26 projects through the opening leading into the chamber bounded by the cylindrical wall 27; and is supported in this position by arcuate portions 29, lateral portions 28, opposing arcuate support portions 32, transverse support portions 30 and ends seating in the opposing adjacent corners of the rectangular compartment 24. The raised center section 26 is proportional to the width or depth of recesses 25, that is, the radius of the arc is such that the raisedcenter section will not lock into the slots or recesses 25 but only seat to provide a detent action whereby the spring will not be deflected beyond its elastic limits upon unseating during a selective operation.

In order to provide such detent action on the index member the raised portion is supported by arcuate portions 29 opposing arc-uate support portions 32 and cross sectional ends, which distribute the stress or deflection on the raised center section to the end portions .30 seating the ends in the opposing adjacent corners 31 of the compartment as shown in Figure 5. The longitudinal dimension of the spring in its inoperative state is shorter than the compartment; this feature facilitates insertion in the compartment 24 since no deflection of the spring is necessary in assembly. Deflection of the spring by the indexed member seats the end portions 30 which remain seated under the static load of the index member 22.

In addition to the force component 33 and resulting deflection of the detent spring 20, indicated in Figure 5, a second lateral component is gadded due to the rotation of the indexed member. This component of force may be beyond the elastic limits of the spring, should be raised center "section 26 lock in arecess 25. Toavoid this, the radius of the are forming the center section is determined proportionally by the depth and width of the recess to provide a detent action without permanently deforming the spring. For a recess of a given width and depth the radius of the arc of the center section may be adjusted as shown in Figure 3 wherein only a portion of said section seats in the recess and abuts only the opposing edges.

In operation the indexed member 22 may be rotated by selectively positioning the control knob 10. Rotation of the index member 22 forces the raised section 26 of the detent spring out of the indexing slot and deflects a spring support of one of the movable contacts 18 which is located in the path of rotation of the operator 23, an eccentric peripheral cam. The detent spring will seat in the next recess along the periphery of the index member whereupon the operator or cam will have deflected the spring support closing a stationary and movable contact 18, 19 completing the circuit from the associated stationary contact terminal to a terminal common to both movable contacts. Further rotation of the control knob in either direction places the cam in an inoperative position opening both circuits; however, positioning the control knob in the direction indicated by the indicia on the raised section housing is preferable since the cam operates at a greater distance along the lever formed by the spring support positioning the movable contacts against their associated stationary contacts.

While certain preferred embodiments of the invention have been specifically disclosed, it is undertsood that the invention is not limited thereto, as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpretation within the terms of the following claims.

What is claimed is:

l. A selector switch comprising; an insulating base having a central recess, a chamber extending through a wall of said base forming a cylindrical wall in said base having a retaining flange projecting into said chamber at the outer edge, an opening taper on the inner edge of said chamber and a rectangular compartment opening into the chamber in the cylindrical wall opposing said taper, a pair of movable contacts, a pair of resilient contact supports aligned with said chamber for mounting the contacts to said base, a cylindrical indexing member seated for rotation in said chamber, an operator comprising an undercut oblong extension projecting axially from said member between said contact supports for operating said contacts; a detent spring having a peaked center section, laterally and arcuately extending side portions having opposing arcing end support portions loosely fitted into opposing lateral sides of said compartment wherein the peaked center section extends into said chamber and the extreme ends are supported on a side of the compartment opposing said opening, recesses formed in the periphery of said indexing member cooperating with said spring to position said operator, said indexing member cooperating with the tapered edge of said chamber for inserting the member past the portion of the detent spring extending into the compartment and statically loading the spring through said peaked center section to deflect said spring and position the end portions into opposing adjacent corners of said compartment upon seating in said chamber.

2. A selector switch comprising, an insulating base having a central recess, a removable cover for said base and recess, a chamber extending through a wall of said base in the form of a cylindrical wall having a retaining flange projecting in said chamber at the outer edge thereof, an opening taper on the inner edge of said wall and a rectangular compartment opening into said chamber in the cylindrical wall opposing said taper, a pair of movable contacts, a pair of resilient contact supports aligned with said chamber for mounting the contacts to said base, a cylindrical indexing member seated for rotation in said chamber, an operator comprising an undercut oblong extension projecting axially from said member between said contact supports for operating said contacts and an undercut portion on the opposite side of said member for rotatably seating said operator in the inner periphery of said flange; a detent spring extending to a peaked center section, including lateral and arcuate side portions and opposing arcuate end support portions and cross sectional ends loosely fitted into said compartment wherein the peaked center section extends into said chamber and the detent spring cross-sectional ends support the remainder of said spring on the wall of the compartment opposing said opening, slots formed in the periphery of said index member parallel to its axis cooperating with said spring to position said operator, said indem'ng member statically loading the spring through said peaked center section to deflect said spring and position the ends into opposing adjacent corners of said compartment.

3. A selector switch comprising, an insulating base having a central recess, a removable cover for said base and recess, a chamber extending through a Wall of said base in the form of a cylinder having a peripheral flange at the outer edge, an opening taper on the inner edge of said chamber and a rectangular compartment opening into said chamber in the cylindrical wall opposing said taper, a pair of movable contacts, a pair of resilient contact supports aligned with said chamber for mounting the contacts to said base, a pair of contacts fixed to said base and disposed in alignment with and on either side of said movable contacts, a cylindrical index member seated for rotation in said chamber and operator comprising an undercut oblong extension projecting axially from said member projecting between said contact supports for o erating said contacts, and an undercut portion on the opposite side of said member rotatably seating said member on the inner periphery of said flange; a detent spring having a peaked center section, lateral arcuate side portions opposing arcuate end support portions and cross sectional ends loosely fitted into said compartment wherein the peaked center section extends into said chamber, slots formed in the periphery of said index member parallel to its axis cooperating with said spring to position said operator, said index member statically loading said spring through said peaked center section to deflect said spring and position the ends into opposing adjacent corners of said compartment.

4. An indexing assembly comprising; a member having indexing notches, a detent spring having a raised center contact section, said center section having a larger radius of curvature than said notches, laterally projecting portions and transversely extending end portions, a housing for said member and said spring providing relative movement of said member including a flat surface seat for said spring and arranged for engaging the ends thereof and biasing the center section against said member for indexing.

5. An indexing device comprising; a cylindrical member having a plurality of longitudinal indexing slots along the periphery thereof, a housing having a cylindrical chamber seating said member for rotation relative to said housing, a rectangular compartment having a longitudinal edge opening into said chamber; a detent spring in said compartment formed without sharply bent portions to have a raised center section of larger lateral dimensions than the slot opening to seat along edges of said slots on the periphery of said cylindrical member and resiliently supported in said chamber by arcuate lateral sections and inversely arcuate end sections seating in opposing adjacent corners of the side opposing said opening in said compartment under the static load produced by said member bearing against and tending to displace said center section from said chamber into said compartment.

6, detent spring comprising; a continuous strip of fiat resilient mateiial formed Without sharply bent portions to have a raised center section, lateral side portions and end support sections, said center section extending laterally and arcuately into the side portions and side portions projecting transversely and arcuately into its respective end portion, said end support portions being formed perpendicular to the longitudinal axis of said spring, said lateral and transversely projecting portions providing opposing arcuate slopes and a transverse dimension to produce compressive spring pressure from the center section for the width of the spring across the end portions within the elastic limit of the spring material.

7. In an indexing assembly, a member having a plurality of indexing recesses in the surface thereof; a detent spring comprising a continuous strip of flat resilient material having a raised center section for engaging the recesses of said member, lateral side portions, transverse end support sections; said center section arcing laterally into the side portions and side portions arcing downwardly into their respective end portions; said center section being formed along parallel arcs having a radii proportional to the depth and width of each recess providing an increase in friction between said center section and member at each recess support means at the extreme ends of said spring; said lateral and downward portions being arcuately sloped to transmit lateral compressive forces at the center section directly to a com pressive force at one of the end portions wherein said end support portions are formed approximately perpendicular to the longitudinal axis of said spring project- 'ing inwardly toward the longitudinal axis of said spring.

8. In an indexing assembly, a member having a plurality of indexing recesses in the surface thereof; a detent Spring comprising a continuous strip resilient material having a raised center section for engaging the recesses of said member, lateral side portions, and end support portions, said center section extending laterally into the side portions and side portions extending downwardly into their respective end portions; said center section being formed along an are having a radius proportional to the depth and width of each recess providing an increase in friction at each recess and wherein the center of said are lies in a vertical plane co-incident with said lateral portions; said lateral and downward extending por tions being arcuately sloped to provide compressive spring pressure resulting from said increase in friction on the portions lateral and in line with the force applied to said center section wherein said end support portions are formed approximately perpendicular to thelongitudinal axis of said spring.

9. In combination, an indexing member having notches in the periphery thereof, a leaf spring member having deflection support portions and an arcuate center section cooperating with said notches to index the relative positions of said members, said support portions projecting laterally and transversely in inverse arcs relative to said center section and on either side of said section, spring support means for abutting the ends and lateral 'outside and support portions of said spring upon deflection to prevent displacement of said end and end support portions beyond the confines of said support means.

10. In combination, an indexing member having notches in the periphery thereof, a leaf spring member having deflection support portions and arcuate center section cooperating with the edges of said notches on the periphery to index the relative positions of said members, said support portions projecting laterally and transversely in inverse arcs relative to said center section and on either side of said section, spring support means for abutting the ends and lateral outside end support portions of said spring upon deflection to prevent displacement of said end and end support portions beyond the confines of said support means.

11. In combination, an indexing member having notches in the periphery thereof, a leaf spring member having deflection support portions and arcuate center section cooperating with the lateral peripheral edges of said notches to index the relative positions of said members wherein the radius of the are forming the center section is large to prevent complete seating in said notches, said support portions projecting laterally and transversely in inverse arcs relative to said center section and on either side of said section, spring support means for abutting the ends and lateral outside end support portions of said spring upon deflection to prevent displacement of said end and end support portions'beyond the confines of said support means.

12. An indexing device comprising; a member having indexing recesses along its periphery, a detent spring having a raised center section for seating in said recesses and support sections extending laterally and transversely to the ends of said spring, means for supporting said spring adjacent said member for relative movement whereby the center section abuts the periphery of said member and the width of said spring is transverse to direction of movement, said support means including means abutting the ends and at least a portion of the outer side of the transverse section when statically loaded by said member whereby lateral and transverse reactive forces are transmitted to the center section of said spring in re sponse to transverse and lateral compressive forces produced by said member on said spring through the raised center section.

-13. An indexing device comprising; a member having indexing recesses along its periphery, a detent spring having a raised center section having an arc radius preventing complete seating and abutting the peripheral edge of said recesses and support sections extending laterally and transversely to the ends of said spring, means for supporting said spring adjacent said member for relative movement whereby the center section abuts the periphery of said member and the width of said spring is transverse to direction of movement, said support means including means abutting the ends and at least a portion of the outer side of the transverse section when statically loaded by said member whereby lateral and transverse reactive forces are transmit-ted to the center section of said spring in response to transverse and lateral compressive forces produced by said member on said spring through the raised center section.

References Cited in the file of this patent UNITED STATES PATENTS 1,467,947 Norviel Sept. 11, 1923 2,262,306 Thompson Nov. 11, 1941 2,462,594 Beal Feb. 22, 1949 2,600,652 Huck June 17, 1952 

